This Core has grown substantially and has been quite successful since its inception as part of the Program Project Grant DK49210. The Core expanded in 1997 to provides services and reagents to members of the Center for Molecular Studies in Digestive and Liver Disease P30DK50306. Within the past two years, Debra Silberg M.D., Ph.D., became the Director of the Core. With the growth of the Core and the addition of the financial support from DK50306, Gary Swain, Ph.D. was hired as the Technical Director. Both Drs. Silberg and Swain have been essential in expanding the scientific aspects of the Core by teaching techniques to the Core members and assisting in the development of protocols for new antibodies for immunohistochemistry. With the addition of two full time technicians, the Core has been able to provide quality services in a timely manner to the members of the Program Project with an overall increase in usage over the past year. The following description of the Core will outline the services provided, including a section that will focus on how each investigator will utilize the Morphology Core (Section 8). In addition, Morphologic data generated by each of the Principle Investigators will be presented as an example of the quality of work that can be expected (Section 9). An important aspect of this Core has been the interactions that have occurred among its members. The Morphology Core is located on the 6th floor of the Clinical Research Building, in rooms adjacent to Drs. Lazar, Stoffers, and Silberg?s laboratories and one floor above Dr. Kaestner?s laboratory and three floors above the laboratory of Dr. Birnbaum. Due to the close location of the Morphology Core, it has become a center for Principal Investigators, fellows and technicians to network while performing immunohistochemistry or using the imaging equipment. Collaborations have been built through these interactions, and we anticipate fostering future collaborations in this way.